Introduction of Enzymatic Polymer Degradation to enhance the Undergraduate Polymer Chemistry Curriculum

Abstract

Changes to the 2015 ACS Guidelines and Evaluation Procedures for Bachelor's Degree Programs included mandatory instruction in polymers and macromolecules for the ACS‐certified degrees. To satisfy this mandate, we have begun developing a series of undergraduate laboratory exercises involving the synthesis, degradation, and characterization of poly(aspartic acid) (PAA). PAA, a biodegradable, water‐soluble synthetic polymer, could potentially replace commonly used poly(acrylic acid), which is a non‐biodegradable polymer that possess environmental risks. In this module of experiments, PAA is prepared in the organic chemistry laboratory course by polymerizing aspartic acid to form poly(succinimide) as an intermediate, which is converted to PAA by base induced ring‐opening. The synthetic PAA, composed of both β‐amide (70%) and α‐amide units (30%), is then transferred to the biochemistry laboratory course for enzymatic biodegradation using two enzymes, PAA hydrolase‐1 (PAAH‐1) and PAA hydrolase‐2 (PAAH‐2). A proposed mechanism suggests that PAAH‐1 hydrolyzes β‐β amide linkages, resulting in oligo (aspartic acid), wherein PAAH‐2 completes the degradation process by cleaving the oligo (aspartic acid) units into monomeric aspartic acid. Current progress on the development of this biochemistry laboratory exercise including overexpression of recombinant PAAH‐1 and PAAH‐2, purification, and characterization will be presented.Support or Funding InformationDUE 1611988